The field of the invention is the field of optical communications and optical fiber transmission and control of light signals.
The field of fiber optic communications has exploded in the last thirty years with inventions which provide optical fibers with low loss over hundreds of kilometers, lasers which are reliable and long lived, and optical amplifiers which remove the need to convert optical signals to electrical signals for amplification and reconversion back to optical signals.
The most common types of optical amplifier are short lengths (1 to 10 meters) of optical fiber doped with ions (typically erbium) which provide gain for optical signals when pumped with a pump laser. The short length of amplifying fiber are spliced into the long length passive fibers which carry the optical signals for tens to hundreds of kilometers between amplification steps. Other optical amplifiers make use of the Raman gain in the silica of the optical fiber. There is no doping of amplifying ions into the silica, since the non-linear properties of the silica itself are used for the amplification.
One recent development of optical fibers is the development of holey fibers, where the fibers are produced with voids or holes filled with air. The holey fibers produce different dispersion characteristics in the optical fibers. References pertinent to the above prior art are: E. J. Woodbury and W. K. Ng, Proc. IRE 50, 2347 (1962); E. J. Woodbury and G. M. Eckhardt, U.S. Pat. No. 3,371,265 (Feb. 27, 1968); M. D. Levenson and S. S. Kano, xe2x80x9cIntroduction to Nonlinear Laser Spectroscopy, Revised Edition,xe2x80x9d Academic Press (San Diego 1988); Y. R. Shen, xe2x80x9cPrinciples of Nonlinear Optics,xe2x80x9d John Wiley and Sons (New York, 1984); G. P. Agrawal, xe2x80x9cNonlinear Fiber Optics,xe2x80x9d Academic Press (San Diego, 1989); A. M. Zheltikov, xe2x80x9cHoley Fibersxe2x80x9d, Physicsxe2x80x94Uspekhi 43, (11) 1125-1136 (2000), Hecht, J.,xe2x80x9cHoley fibers cut their lossesxe2x80x9d, Technology Review, Apr. 17, 2001; Kafka, et al., U.S. Pat. No. 6,236,779, and Islam, et al., U.S. Pat. No. 6,239,903. The above references and patents are hereby incorporated by reference, including incorporated material.
It is an object of the invention to produce optical fiber control means to control optical signals. It is an object of the invention to produce optical fiber control means to amplify optical signals. It is an object of the invention to produce optical fiber control means to attenuate optical signals. It is an object of the invention to produce optical fiber control means to control optical signals selectively, so that one or more optical signals of a large plurality of signals are controlled while others of the plurality are not controlled. It is an object of the invention to produce optical fiber control means to control dispersion of optical signals. It is an object of the invention to produce optical fiber control means to shift power from one optical signal to another optical signal. It is an object of the invention to produce optical fiber control means to perform logical operations on two optical signals. It is an object of the invention to produce optical fiber apparatus to control optical signals. It is an object of the invention to produce optical fiber methods to control optical signals. It is an object of the invention to produce optical fiber systems to control optical signals.
The present invention is a system, apparatus and method of use of an optical fiber having voids in the cladding and/or core, wherein the voids are filled with a fluid having non-linear optical properties for the control of light signals. Non linear optical properties are anticipated to be Raman gain for amplifying or attenuating optical signals, and resonant and non-resonant non-linear index of refraction for 4 wave parametric generation, amplification, and control of optical signals.